Adaptive SRRC Roll-Off in Single-Carrier Blocks for Spectral Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional single carrier transmission systems face challenges in achieving ultra-reliable and low latency communication while maintaining spectral efficiency, as high roll-off factors used to reduce interference result in increased bandwidth consumption and spectral efficiency loss.
Innovation Solution
Implementing an adaptive roll-off factor in a block using square root Raised Cosine (SRRC) filters with varying roll-off factors for different symbols, minimizing out-of-band emission and spectral efficiency loss, and optimizing roll-off factors from center to edge pulses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high roll-off factor is used for Raised Cosine pulses, then out of band emission is reduced and reliability increases, but spectral efficiency is lost and bandwidth increases
Solution Approach 1:
The patent applies different roll-off factors to different positions within a block of symbols. Edge symbols use higher roll-off factors to reduce out of band emission, while center symbols use lower roll-off factors to maintain spectral efficiency. This local differentiation resolves the contradiction by optimizing each position's contribution to overall system performance.
Solution Approach 2:
The patent divides the transmission block into different segments (edge symbols vs. center symbols) and applies different filtering parameters to each segment. This segmentation allows the system to handle the conflicting requirements of reliability and spectral efficiency in different parts of the transmission, achieving both goals simultaneously.
2Object-generated harmful factors
If high roll-off factor is used for Raised Cosine pulses, then out of band emission is reduced, but bandwidth consumption increases
Solution Approach 1:
The patent applies higher roll-off factors only to edge symbols where out of band emission is most problematic, while using lower roll-off factors for center symbols. This localized approach reduces overall out of band emission without requiring all symbols to consume excess bandwidth, thus resolving the contradiction between emission reduction and bandwidth efficiency.
3Device complexity
If fixed roll-off factor is used in single carrier transmission, then implementation is simple, but inter-symbol interference occurs and spectral efficiency is reduced
Solution Approach 1:
The patent transitions from a static fixed roll-off factor to a dynamic adaptive roll-off factor that changes based on symbol position within the block. This dynamic approach allows the system to optimize spectral efficiency by using lower roll-off factors for center symbols while maintaining simplicity through a predetermined pattern, resolving the contradiction between complexity and performance.
Data Source
AI summary
A single carrier transmission that minimizes spectral efficiency loss and reduces out of band emission by using adaptive filtering in a block where different filter parameters are used for different symbols within a block.